Question: Solve for $a$ : $a + 28 = -10$
Solution: Subtract $28$ from both sides: $ \begin{eqnarray} \\ a + 28 &=& -10 \\ \\ {-28} && {-28} \end{eqnarray} $ $ \begin{eqnarray} \hphantom{28 + a} &\hphantom{=}& \hphantom{-10} \\ a &=& -10 {- 28} \\ \end{eqnarray} $ Simplify. $ a = -38$